Conversations about Paul's physical conditioning always come up. Paul looks great right now, and he generally does. But, Paul does not have a Ray Allen type physique. It kind of comes and goes a little bit with him, as far as how lean he looks.
I don't think it's as linear as he looks good early in the season, and then starts to look flabbier as the season progresses. I actually feel like he goes through different stretches throughout a season depending on nagging injuries and when his little rests happen.
I've got to mention, though that Paul Pierce has been one of the league's most durable players among upper echelon guys of the last decade. Except for the season from hell that he basically took off for some long term respite on his body, Paul had very few major injuries over his 10+ years in the league. His ability to take care of his body over the years will absolutely be one of the things that stand out when our captain's legacy is written.